Efficacy of the Laryngeal Tube in General Anesthesia / 대한마취과학회지

ABSTRACT

BACKGROUND: A prototype airway management device, a laryngeal tube, has been recently introduced in Korea. This study was designed to assess the efficacy of the laryngeal tube for airway management under general anesthesia. METHODS: We studied thirty-six ASA physical status I and II patients undergoing general anesthesia. Anesthesia was induced with sleep dose propofol 2.0 mg/kg i.v., supplemented with fentanyl 1 microgram/kg, and maintained with 50% nitrous oxide and propofol. After inserting the laryngeal tube, its cuff was inflated using a balloon cuff gauge until the intracuff pressure reached approximately 65 cmH2O. Adequacy of ventilation was assessed by observing the end tidal carbon dioxide wave form, chest wall movement and by stethoscope auscultation. Oropharyngeal leak pressure was also measured. Changes in heart rate, blood pressure, end-tidal carbon dioxide, airway pressure and oxygen saturation before induction, before insertion, 2, 5 and 10 minutes after insertion and 5 minutes after incision were recorded. RESULTS: The first time success rate at achieving an effective airway was 30 in 36 (83%). The mean leak pressure was 22.9+/-4.6 mmHg. Heart rate, blood pressure, oxygen saturation, end-tidal carbon dioxide and airway pressure values remained stable during laryngeal tube insertion and during the surgical procedure. CONCLUSIONS: We conclude that the laryngeal tube is easy to place, allows adequate ventilation and has a lower incidence of complications. It may offer an alternative device for the oxygenation of non-intubated patients undergoing general anesthesia.